Photoelectric device structure and photoelectric device electric leakage test method

Abstract

The invention discloses a photoelectric device structure and a photoelectric device electric leakage test method, relates to the technical field of semiconductor photoelectricity, and aims to solve the problem of low solving efficiency of electric leakage of a semiconductor photoelectric device in the prior art. The substrate comprises a substrate front surface and a substrate back surface; the active region is formed on the front surface of the substrate; the central region is formed on the back surface of the substrate; the at least one first protection ring is arranged around the active region; the doping type of the first protection ring is the same as or opposite to that of the active region; the photoelectric device electric leakage test method comprises the steps of obtaining basic data of a photoelectric device structure; the basic data at least comprises structure type information of the photoelectric device structure; classifying the photoelectric device structures based on the basic data to obtain different types of photoelectric devices; and testing the different types of photoelectric devices to obtain leakage current data of the different types of photoelectric devices in a preset voltage range.

Description

TECHNICAL FIELD

[0001] The present application relates to the field of semiconductor optoelectronic technology, and in particular to an optoelectronic device structure and an optoelectronic device leakage test method. BACKGROUND

[0002] In various semiconductor optoelectronic devices, leakage current is one of the elements that most affects the performance of the optoelectronic device. For example, in a photodetector, leakage current can cause great damage to the most important performance of the photodetector, i.e., energy resolution. The main part of the leakage current of the optoelectronic device is surface leakage current, and the surface leakage current often occurs at the edge of the optoelectronic device.

[0003] In previous studies, it has been found that the leakage of the semiconductor optoelectronic device is mainly from the edge of the optoelectronic device. This is because the edge of the PN junction is often a place where the doping changes, and a great local electric field often gathers at this sharp edge. Therefore, when a reverse bias voltage is applied, the local electric field at the edge will reach the breakdown voltage earlier than the internal active region, causing the optoelectronic device to be broken down prematurely. In addition, the large local electric field at the edge will cause large edge leakage, increasing the total leakage current of the optoelectronic device. Therefore, solving the problem of edge leakage of the optoelectronic device is a key step to improve the performance of the optoelectronic device.

[0004] A guard ring is an effective way to solve the problem of edge leakage. It can make the electric field at the edge of the semiconductor optoelectronic device smooth. In practical applications, the guard ring is often set as a nested guard ring unit. The width of these guard rings gradually decreases as the distance from the active region increases, and the spacing gradually widens, like a layer of stairs, gradually "unloading" the sharp electric field at the edge of the active region, which achieves the smoothing of the edge electric field.

[0005] Currently, research on the effect of the guard ring on the performance of the semiconductor optoelectronic device mainly focuses on the number of guard rings and the spacing between multiple guard rings. The effect of other aspects of the guard ring on the leakage performance of the semiconductor optoelectronic device has not been involved and analyzed.

[0006] There is an urgent need in the art to analyze the effect of the guard ring on the leakage performance of the semiconductor optoelectronic device from other aspects of the guard ring in order to obtain a better solution to the leakage of the semiconductor optoelectronic device. SUMMARY

[0007] The purpose of the present application is to provide an optoelectronic device structure and an optoelectronic device leakage test method for improving the efficiency of solving the leakage of the semiconductor optoelectronic device.

[0008] In order to achieve the above-mentioned purpose, the present application provides the following technical solutions:

[0009] In a first aspect, the present application provides an optoelectronic device structure, comprising:

[0010] a substrate, comprising a substrate front surface and a substrate back surface;

[0011] an active region formed on the substrate front surface;

[0012] a central region formed on the substrate back surface;

[0013] and at least one first guard ring disposed around the active region; the first guard ring has a same or opposite doping type as the active region.

[0014] In a second aspect, the present application provides a method for testing leakage of a photoelectric device, the method being used for testing leakage of the photoelectric device structure as described above, and the method comprising:

[0015] obtaining basic data of the photoelectric device structure; the basic data at least comprises structure type information of the photoelectric device structure;

[0016] classifying the photoelectric device structure based on the basic data, to obtain photoelectric devices of different types;

[0017] testing the photoelectric devices of different types, to obtain leakage current data of the photoelectric devices of different types within a preset voltage range.

[0018] Compared with the prior art, the photoelectric device structure and the method for testing leakage of the photoelectric device provided by the present application form a photoelectric device structure of a different type from the prior art by disposing a guard ring having a same or opposite doping type as the active region around the active region of the substrate, and based on this, test corresponding leakage current data of photoelectric devices of different types within a preset voltage range, to obtain leakage performance of photoelectric devices of different types, and improve the solution efficiency of leakage of semiconductor photoelectric devices. BRIEF DESCRIPTION OF DRAWINGS

[0019] The accompanying drawings, which are included to provide a further understanding of the present application, constitute a part of the present application and illustrate embodiments of the present application and the explanation of the present application, and do not constitute an improper limitation on the present application. In the drawings:

[0020] Figure 1 a photoelectric device structure schematic diagram provided by an embodiment of the present application;

[0021] Figure 2 a photoelectric device structure schematic diagram provided by an embodiment of the present application;

[0022] Figure 3 a photoelectric device structure schematic diagram provided by an embodiment of the present application;

[0023] Figure 4A schematic diagram of a photoelectric device structure according to an embodiment of the present application;

[0024] Figure 5 A schematic diagram of a photoelectric device structure according to an embodiment of the present application;

[0025] Figure 6 A schematic diagram of a photoelectric device structure according to an embodiment of the present application;

[0026] Figure 7 A schematic diagram of a photoelectric device structure according to an embodiment of the present application;

[0027] Figure 8 A schematic diagram of a photoelectric device structure according to an embodiment of the present application;

[0028] Figure 9 A schematic diagram of a photoelectric device structure according to an embodiment of the present application;

[0029] Figure 10 A schematic diagram of a photoelectric device structure according to an embodiment of the present application;

[0030] Figure 11 A schematic diagram of a photoelectric device structure according to an embodiment of the present application;

[0031] Figure 12 A schematic diagram of a photoelectric device structure according to an embodiment of the present application;

[0032] Figure 13 A schematic diagram of a photoelectric device structure according to an embodiment of the present application;

[0033] Figure 14 A schematic diagram of a photoelectric device structure according to an embodiment of the present application;

[0034] Figure 15 A schematic diagram of a photoelectric device structure according to an embodiment of the present application;

[0035] Figure 16 A schematic diagram of a photoelectric device structure according to an embodiment of the present application;

[0036] Figure 17The schematic diagram of the change curve of the active region leakage current with the change of the bias voltage under different surface recombination rates of the P-type guard ring optoelectronic device provided in the first embodiment of the present application is shown in FIG. 1.

[0037] Figure 18 The schematic diagram of the change curve of the guard ring leakage current with the change of the bias voltage under different surface recombination rates of the P-type guard ring optoelectronic device provided in the first embodiment of the present application is shown in FIG. 2.

[0038] Figure 19 The schematic diagram of the change curve of the active region leakage current with the change of the bias voltage under different surface recombination rates of the N-type guard ring optoelectronic device provided in the first embodiment of the present application is shown in FIG. 3.

[0039] Figure 20 The schematic diagram of the change curve of the guard ring leakage current with the change of the bias voltage under different surface recombination rates of the N-type guard ring optoelectronic device provided in the first embodiment of the present application is shown in FIG. 4.

[0040] Figure 21 The schematic diagram of the comparison result of the leakage test of the P-type guard ring optoelectronic device and the N-type guard ring optoelectronic device provided in the first embodiment of the present application under the same target spacing and the same surface recombination rate is shown in FIG. 5.

[0041] Reference signs:

[0042] 10-substrate; 11-active region; 12-center region; 13-first guard ring; 14-second guard ring. EMBODIMENT

[0043] In order to clearly describe the technical solutions of the embodiments of the present application, in the embodiments of the present application, the same items or similar items with basically the same functions and effects are distinguished by using "first", "second", etc. For example, the first threshold value and the second threshold value are only used to distinguish different threshold values, and do not limit the order. Those skilled in the art can understand that "first", "second", etc. do not limit the number and execution order, and "first", "second", etc. also do not mean that they must be different.

[0044] It should be noted that in the present application, the words "exemplary" or "for example" are used to mean serving as an example, instance, or illustration. Any embodiment or design solution described as "exemplary" or "for example" in the present application should not be interpreted as being more preferred or having more advantages than other embodiments or design solutions. Rather, the words "exemplary" or "for example" are used in the sense of presenting a specific example.

[0045] In the present application, "at least one" means one or more, and "multiple" means two or more. The "and / or" describes the association relationship of the associated objects, which means that there can be three kinds of relationships.

[0046] As shown in Figure 1 , the embodiment of the present application provides an optoelectronic device structure, which can include:

[0047] a substrate 10, the substrate 10 includes a substrate front surface and a substrate back surface;

[0048] an active region 11 formed on the substrate front surface;

[0049] a central region 12 formed on the substrate back surface;

[0050] and at least one first guard ring 13 arranged around the active region 11; the doping type of the first guard ring is the same as or opposite to the doping type of the active region.

[0051] Optionally, the material of the substrate 10 is any one of silicon, germanium, silicon carbide, potassium oxide and gallium arsenide.

[0052] Optionally, the substrate 10 can be a high-resistance N-type silicon substrate, the doping type of the active region on the front surface of the silicon substrate is P+, and the doping type of the central region on the back surface of the silicon substrate is N+.

[0053] Optionally, in the overhead direction along the front surface of the substrate 10, the active region 11 can be circular, and the first guard ring 13 is a concentric circular ring concentric with the active region 11, as shown in Figure 2 . It should be noted that the radius of the first guard ring is greater than the radius of the active region.

[0054] Optionally, in the overhead direction along the front surface of the substrate 10, the active region 11 can be a regular polygon, and correspondingly, the first guard ring 13 is also a regular polygon ring.

[0055] The optoelectronic device structure can further include: at least one second guard ring 14 arranged around the central region 12; the doping type of the second guard ring is the same as or opposite to the doping type of the central region.

[0056] Optionally, in the overhead direction along the front surface of the substrate 10, the central region 12 can be circular, and the second guard ring 14 is a concentric circular ring concentric with the central region 12, as shown in Figure 3 . It should be noted that the radius of the second guard ring 14 is greater than the radius of the central region 12. In addition, the size of the central region 12 and the size of the active region 11 can have no relevance.

[0057] Optionally, in the overhead direction along the front surface of the substrate 10, the central region 12 can be a regular polygon, and correspondingly, the second guard ring 14 is also a regular polygon ring.

[0058] All the following examples are further illustrated with the substrate 10 as an N-type silicon substrate, the active region 11 as P+, the central region 12 as N+, the active region 11 as a circle, the central region 12 as a circle, and the guard ring as a circular ring. It is to be noted that all the examples do not limit the substrate material, the active region doping type, and the central region doping type.

[0059] Optionally, when the doping type of the first guard ring 13 is the same as the doping type of the active region 11, the optoelectronic device structure is, for example, as shown in FIG. 2, wherein the active region 11 on the N-type silicon substrate is P+, the doping type of the first guard ring 13 is P+ (the first guard ring 13 is a P-type guard ring), the doping type of the central region 12 is N+, and the silicon substrate 10 has no second guard ring 14 on the back surface. Figure 4

[0060] Optionally, when the doping type of the first guard ring 13 is opposite to the doping type of the active region 11, the optoelectronic device structure is, for example, as shown in FIG. 3, wherein the active region 11 on the N-type silicon substrate is P+, the doping type of the first guard ring 13 is N+ (the first guard ring 13 is an N-type guard ring), the doping type of the central region 12 is N+, and the silicon substrate 10 has no second guard ring 14 on the back surface. Figure 5

[0061] Optionally, when the doping type of the second guard ring 14 is the same as the doping type of the active region 11, the optoelectronic device structure is, for example, as shown in FIG. 4, wherein the active region 11 on the N-type silicon substrate is P+, the doping type of the first guard ring 13 is P+ (the first guard ring 13 is a P-type guard ring), the doping type of the central region 12 is N+, and the doping type of the second guard ring 14 is N+ (the second guard ring 14 is an N-type guard ring). Figure 6 Optionally, when the doping type of the second guard ring 14 is the same as the doping type of the active region 11, the optoelectronic device structure is, for example, as shown in FIG. 5, wherein the active region 11 on the N-type silicon substrate is P+, the doping type of the first guard ring 13 is N+ (the first guard ring 13 is an N-type guard ring), the doping type of the central region 12 is N+, and the doping type of the second guard ring 14 is N+ (the second guard ring 14 is an N-type guard ring).

[0062] Figure 7 Optionally, when the doping type of the second guard ring 14 is opposite to the doping type of the active region 11, the optoelectronic device structure is, for example, as shown in FIG. 6, wherein the active region 11 on the N-type silicon substrate is P+, the doping type of the first guard ring 13 is N+ (the first guard ring 13 is an N-type guard ring), the doping type of the central region 12 is N+, and the doping type of the second guard ring 14 is P+ (the second guard ring 14 is a P-type guard ring).

[0063] Optionally, when the doping type of the second guard ring 14 is opposite to the doping type of the active region 11, the optoelectronic device structure is, for example, as shown in FIG. 7, wherein the active region 11 on the N-type silicon substrate is P+, the doping type of the first guard ring 13 is N+ (the first guard ring 13 is an N-type guard ring), the doping type of the central region 12 is N+, and the doping type of the second guard ring 14 is P+ (the second guard ring 14 is a P-type guard ring). Figure 8 ​​​As shown, the active region 11 on the N-type silicon substrate is doped as P+, the first guard ring 13 is doped as N+ (the first guard ring 13 is an N-type guard ring), the central region 12 is doped as N+, and the second guard ring 14 is doped as P+ (the second guard ring 14 is a P-type guard ring).

[0064] Optionally, when the doping type of the second guard ring 14 is the same as the doping type of the active region 11, the optoelectronic device structure is, for example Figure 9 As shown, the active region 11 on the N-type silicon substrate is doped as P+, the first guard ring 13 is doped as P+ (the first guard ring 13 is a P-type guard ring), the central region 12 is doped as N+, and the second guard ring is doped as P+ (the second guard ring is a P-type guard ring).

[0065] The embodiment of the present application also provides an optoelectronic device leakage test method, which can be used for leakage test on the optoelectronic device structure in any of the above embodiments, such as Figure 10 As shown, the optoelectronic device leakage test method can include:

[0066] Step 110, obtaining basic data of the optoelectronic device structure; the basic data at least includes structure type information of the optoelectronic device structure;

[0067] Specifically, the structure type information can include: the doping type of the first guard ring and the second guard ring information; further, the second guard ring information can include: whether the second guard ring exists and the doping type of the second guard ring; the doping type can be P+ or N+.

[0068] Step 120, classifying the optoelectronic device structure based on the basic data, to obtain different types of optoelectronic devices;

[0069] Step 120 can specifically include:

[0070] According to the doping type of the first guard ring and the second guard ring information, the optoelectronic device whose doping type of the first guard ring is the same as the doping type of the active region and the substrate back surface has no second guard ring is divided into a first type of optoelectronic device, for example Figure 4 As shown;

[0071] The optoelectronic device whose doping type of the first guard ring is opposite to the doping type of the active region and the substrate back surface has no second guard ring is divided into a second type of optoelectronic device, for example Figure 5 As shown;

[0072] The optoelectronic device whose doping type of the first guard ring is the same as the doping type of the active region, the substrate back surface has a second guard ring, and the doping type of the second guard ring is the same as the doping type of the substrate back surface is divided into a third type of optoelectronic device, for example Figure 6 As shown;

[0073] The optoelectronic device with the first guard ring having the same doping type as the active region, the second guard ring on the back surface of the substrate, and the second guard ring having the opposite doping type to the back surface of the substrate is classified as the fourth type of optoelectronic device, for example Figure 9 as shown.

[0074] The optoelectronic device with the first guard ring having the opposite doping type to the active region, the second guard ring on the back surface of the substrate, and the second guard ring having the same doping type to the back surface of the substrate is classified as the fifth type of optoelectronic device, for example Figure 7 as shown.

[0075] The optoelectronic device with the first guard ring having the opposite doping type to the active region, the second guard ring on the back surface of the substrate, and the second guard ring having the opposite doping type to the back surface of the substrate is classified as the sixth type of optoelectronic device, for example Figure 8 as shown.

[0076] Step 130, testing the different types of optoelectronic devices to obtain the leakage current data of the different types of optoelectronic devices in the preset voltage range.

[0077] Specifically, when there is only one first guard ring around the active region, the distance between the first guard ring and the active region is determined as the target spacing.

[0078] Optionally, step 130 can specifically include: testing to obtain the active region leakage current data of each type of optoelectronic device corresponding to each type of optoelectronic device in the preset voltage (preset bias voltage) range under different (for example, M) target spacings; M is a positive integer greater than or equal to 1.

[0079] Optionally, step 130 can specifically include: testing to obtain the active region leakage current data of each type of optoelectronic device corresponding to each type of optoelectronic device in the preset voltage (preset bias voltage) range under different (for example, M) target spacings; M is a positive integer greater than or equal to 1.

[0080] Optionally, step 130 can specifically include: testing to obtain the active region leakage current data of each type of optoelectronic device corresponding to each type of optoelectronic device in the preset voltage (preset bias voltage) range under the same target spacing and the same surface recombination rate.

[0081] Optionally, step 130 can specifically include: testing to obtain the active region leakage current data of each type of optoelectronic device corresponding to each type of optoelectronic device in the preset voltage (preset bias voltage) range under the same target spacing and the same surface recombination rate.

[0082] Optionally, the step 130 can specifically include: testing and obtaining active region leakage current data of each type of optoelectronic device under different surface recombination velocities within a preset voltage (preset bias voltage) range.

[0083] Optionally, the step 130 can specifically include: testing and obtaining active region leakage current data of each type of optoelectronic device under different surface recombination velocities within a preset voltage (preset bias voltage) range and corresponding leakage current data on the guard ring.

[0084] In a specific embodiment one, the active region on the N-type silicon substrate is doped as P+, the first guard ring is doped as P+ (the first guard ring is a P-type guard ring), the center region is doped as N+, and the first type of optoelectronic device (for example, a photodetector) without a second guard ring on the back of the silicon substrate is selected as one of the test objects. The first type of optoelectronic device can also be referred to as a P-type guard ring optoelectronic device. Figure 4 In a specific embodiment two, the active region on the N-type silicon substrate is doped as P+, the first guard ring is doped as N+ (the first guard ring is an N-type guard ring), the center region is doped as N+, and the second type of optoelectronic device without a second guard ring on the back of the silicon substrate is selected as one of the test objects. The second type of optoelectronic device can also be referred to as an N-type guard ring optoelectronic device. The P-type guard ring optoelectronic device and the N-type guard ring optoelectronic device are tested and compared. The optoelectronic device in this embodiment can be a photodetector.

[0085] First, by changing the distance (target distance) between the first guard ring and the active region, the influence of the target distance on the leakage performance of the photodetector is analyzed, the performance is characterized by leakage current, and active region leakage current (active region current) data of the two types of optoelectronic devices under different target distances within a preset voltage (preset bias voltage) range are tested and obtained. The power connection mode of the detector is that the active region and the first guard ring are grounded, and the back electrode voltage can be scanned from 0V to 100V, that is, the preset bias voltage range in this embodiment is [0V, 100V].

[0086] Three different target distances are set, which are 10μm, 40μm, and 70μm.

[0087] The leakage current data test results of the P-type guard ring optoelectronic device with different target distances are shown in Figure 11 As the distance between the P-type guard ring and the active region increases, the active region leakage current of the P-type guard ring optoelectronic device expands.

[0088] It should be noted that the active region leakage current in each embodiment and the active region current in the vertical coordinate of the drawing are the same, and the leakage current on the guard ring in each embodiment and the guard ring current in the vertical coordinate of the drawing are the same.

[0089] Leakage current test results of N-type guard ring optoelectronic devices with different target spacings are as follows: Figure 12 As shown, it can be seen that the N-type guard ring optoelectronic device does not exhibit the characteristics described above. Figure 11 The phenomenon observed is that changes in the target spacing have almost no effect on the leakage current in the active region, and the three curves nearly overlap.

[0090] This change in the P-type guard ring optoelectronic device can be explained as follows: the closer the P-type guard ring is to the active region, the more obvious its protective effect, which can distribute the current and reduce the electric field for the active region. However, as the target spacing increases, this protective effect is significantly weakened. As mentioned earlier, the guard ring's weakening of the large electric field at the edge of the active region is not only reflected in reducing its electric field strength, but also in transferring the electric field from the original edge of the active region to one side of the guard ring. From the comparison diagram of the electric field at different target spacings, we can see that when the distance between the guard ring and the active region is large, the large electric field at the edge is located between the active region and the left edge of the first guard ring, that is, at the edge of the active region; while when the spacing decreases, the large electric field at the edge not only becomes weaker, but also shifts to the right edge of the first guard ring. This precisely reflects the principle of the P-type guard ring's function.

[0091] To understand why the N-type guard ring is unaffected by the target spacing, it is necessary to analyze the internal structure of the optoelectronic device. Therefore, the potential distribution of the two types of optoelectronic devices under a 100V bias voltage was captured, and a tangent was drawn at a distance of 0.2μm from the front surface. The magnitude of the potential on the tangent was extracted to compare the internal mechanism of the N-type guard ring with that of the P-type guard ring.

[0092] Figure 13 The potential distribution of a P-type guard ring optoelectronic device at a bias voltage of 100V is presented. Figure 13 Potential distribution in the substrate when the distance between the middle guard ring and the active region is 40 micrometers; Figure 14 A comparison of potential values ​​at a distance of 0.2 micrometers from the front surface of the device shows three different spacings. It can be seen that the P-type guard ring absorbs the potential of the active region, and in subsequent guard rings, the potential gradually increases in a step-like manner, eventually becoming almost equal to the applied bias voltage. However, in the 70μm spacing optoelectronic device with a larger leakage current, the potential at its outermost edge does not rise to near the applied bias voltage. This indicates that the edge of the depletion region extends to the outermost position, thus introducing a large number of electron-hole pairs generated by defects at the edge cutting point, leading to an increase in leakage current. Furthermore, when the spacing between the active region and the P-type guard ring increases, the potential shows an upward trend between the active region and the first guard ring. Since the first guard ring is grounded, the potential is pulled back to 0. However, when the spacing is small, the potential rise is very short; the potential of the active region is almost directly integrated with the first guard ring, only starting to rise again on the right side of the first guard ring. This demonstrates the role of the P-type guard ring in transferring the electric field at the edge of the active region.

[0093] Figure 15 The potential distribution in the substrate for N-type guard ring photoelectric device at 100V bias voltage, Figure 15 The electric field distribution in the substrate when the distance between the guard ring and the active region is 40 microns; Figure 16 The potential values of three distances at 0.2 microns from the front surface of the device are compared. It is completely different from the P-type guard ring. As can be seen from the structure file, the potential of the P-type guard ring is constantly rising outward from the guard ring; but the potential of the N-type guard ring structure is almost 0 throughout the multiple guard ring range. After looking at the potential values, it was found that although its potential also presents a slight ladder shape, the highest value is only about 2.5V, which is much lower than the potential value of nearly 100V on the P-type guard ring, so it can be ignored. After changing the distance between the guard ring and the active region, its potential also changes only in a very small range, with little effect, and the potential on its guard ring can be directly treated as 0. It is this phenomenon of lowering the potential in a large range that makes the slight movement of the position of the first guard ring have little effect on the potential distribution inside. That is, the function of the N-type guard ring to lower the potential in a large range makes the photoelectric device insensitive to changes in the position of the guard ring.

[0094] Secondly, test the influence of passivation effect on photoelectric device, which can be summarized as the influence of surface recombination rate change on photoelectric device in simulation test. Still choose the leakage current as the characterization standard, test the corresponding active region leakage current data of P-type guard ring photoelectric device and N-type guard ring photoelectric device under different surface recombination rates in the preset bias voltage range. In the first embodiment, the surface recombination rate is simulated to be 1×102cm / s, 1×103cm / s and 1×104cm / s, and the changes of the active region leakage current of the two photoelectric devices are tested.

[0095] The change of the active region leakage current of the P-type guard ring photoelectric device with the bias voltage is shown in Figure 17 The change of the leakage current on the guard ring of the P-type ring photoelectric device with the bias voltage is shown in Figure 18As shown. According to relevant knowledge, the magnitude of the leakage current at the PN junction interface is directly proportional to the surface recombination rate. In the simulation test of Specific Implementation Method 1, a tenfold increase in the surface recombination rate results in a tenfold increase in the total leakage current. From the simulation results, we can see that the vast majority of this increase in leakage current occurs at the guard ring, with only a small portion occurring in the active region. The protective effect of the P-type guard ring on the active region is manifested in the following way: without a guard ring, the leakage current directly passes through the active region; however, with a guard ring, a large portion of the leakage current exits through the guard ring instead of passing through the active region. This conclusion is consistent with the simulation results. Therefore, this simulation provides a clear visual demonstration of the guard ring's protective effect on the active region regarding interface leakage current.

[0096] Then according to Figure 19 and Figure 20 Let's examine the case of N-type guard ring optoelectronic devices. For example... Figure 19 As shown, after the surface recombination rate of the optoelectronic device changes, the leakage current in the active region of the N-type guard ring optoelectronic device does not change significantly, and the three curves almost overlap. This indicates that the N-type guard ring optoelectronic device once again shields the influence of external conditions.

[0097] The simulation results above reveal a key characteristic of N-type guard ring optoelectronic devices: the inherent properties of the N-type guard ring create a wide potential coverage area. If the P-type guard ring acts as an auxiliary element for the active region, then the N-type guard ring functions like a switch. Once placed around the active region, it directly reduces the leakage current, rendering minor changes in external conditions ineffective. This leads to an important conclusion about N-type guard rings: they are less susceptible to external influences, shielding against changes in external conditions within a certain range, and are particularly less dependent on the passivation layer. They function more like a functional structure, exhibiting stable performance under various external conditions. This indicates that their manufacturing requires less stringent process conditions and are suitable for use in harsher environments. This is a significant advantage of N-type guard ring optoelectronic devices.

[0098] Finally, after comparing the different reaction mechanisms of N-type and P-type guard ring optoelectronic devices under various changing conditions, we need to conduct a side-by-side comparison of the two optoelectronic devices under the same conditions. The main performance comparison between different detectors lies in leakage current and energy resolution. With the distance between the first guard ring and the active region of both optoelectronic devices set to 40 μm and the surface recombination rate set to 1 × 10⁴ cm / s, the final IV curves of the two are compared as follows: Figure 21As shown, under the same conditions, the leakage current of the N-type guard ring optoelectronic device is slightly lower than that of the P-type guard ring optoelectronic device. Therefore, the N-type guard ring is less susceptible to external influences and can better protect the active region. The protection of the active region by the N-type guard ring has practical engineering value. This is also the significance of providing different optoelectronic device structures in the embodiments of this invention.

[0099] Although the invention has been described herein in conjunction with various embodiments, those skilled in the art will understand and implement other variations of the disclosed embodiments by reviewing the accompanying drawings, the disclosure, and the appended claims in carrying out the claimed invention. In the claims, the word "comprising" does not exclude other components or steps, and "a" or "an" does not exclude a plurality. A single processor or other unit can implement several functions listed in the claims. While different dependent claims may recite certain measures, this does not mean that these measures cannot be combined to produce good results.

[0100] Although the invention has been described in conjunction with specific features and embodiments, it is obvious that various modifications and combinations can be made therein without departing from the spirit and scope of the invention. Accordingly, this specification and drawings are merely exemplary descriptions of the invention as defined by the appended claims, and are considered to cover any and all modifications, variations, combinations, or equivalents within the scope of the invention. Clearly, those skilled in the art can make various alterations and modifications to the invention without departing from its spirit and scope. Thus, if such modifications and modifications of the invention fall within the scope of the claims and their equivalents, the invention is also intended to include such modifications and modifications.

Claims

1. An optoelectronic device structure, characterized by The structure comprises: a substrate, the substrate comprising a substrate front surface and a substrate back surface; an active region formed on the substrate front surface; a central region formed on the substrate back surface; and at least one first guard ring disposed around the active region; the first guard ring having a same or opposite doping type as the active region.

2. The optoelectronic device structure of claim 1, wherein, Further comprising: at least one second guard ring disposed around the central region; the second guard ring having a same or opposite doping type as the central region.

3. The optoelectronic device structure of claim 1, wherein, In a top-down view along the substrate front surface, the active region is circular; the first guard ring is a concentric circular ring concentric with the active region; the first guard ring has a radius greater than that of the active region.

4. The optoelectronic device structure of claim 2, wherein, the central region is circular; the second guard ring is a concentric circular ring concentric with the central region; the second guard ring has a radius greater than that of the central region.

5. The optoelectronic device structure of claim 2, wherein, In a top-down view along the substrate front surface, the active region or the central region is a regular polygon; the first guard ring or the second guard ring is a regular polygon ring.

6. The optoelectronic device structure of claim 1, wherein, The substrate is made of any one of silicon, germanium, silicon carbide, potassium oxide, and gallium arsenide.

7. A method of testing for leakage in an optoelectronic device, the method comprising: The method is used for leakage testing of the optoelectronic device structure of any one of claims 1-6, and the method comprises: obtaining basic data of the optoelectronic device structure; the basic data at least comprises structure type information of the optoelectronic device structure; classifying the optoelectronic device structure based on the basic data to obtain different types of optoelectronic devices; testing different types of optoelectronic devices to obtain leakage current data of different types of optoelectronic devices in a preset voltage range.

8. The method of claim 7, wherein the step of applying a voltage comprises applying a voltage of about 1 volt to about 10 volts. The structure type information comprises a doping type of the first guard ring and second guard ring information; The classifying the optoelectronic device structure based on the basic data to obtain different types of optoelectronic devices comprises: dividing, according to the doping type of the first guard ring and the second guard ring information, the optoelectronic device with the same doping type of the first guard ring and the active region and without the second guard ring on the substrate back surface into a first type of optoelectronic device; dividing, according to the doping type of the first guard ring and the second guard ring information, the optoelectronic device with the opposite doping type of the first guard ring and the active region and without the second guard ring on the substrate back surface into a second type of optoelectronic device; dividing, according to the doping type of the first guard ring and the second guard ring information, the optoelectronic device with the same doping type of the first guard ring and the active region, with the second guard ring on the substrate back surface, and with the same doping type of the second guard ring and the substrate back surface into a third type of optoelectronic device; dividing, according to the doping type of the first guard ring and the second guard ring information, the optoelectronic device with the same doping type of the first guard ring and the active region, with the second guard ring on the substrate back surface, and with the opposite doping type of the second guard ring and the substrate back surface into a fourth type of optoelectronic device; dividing, according to the doping type of the first guard ring and the second guard ring information, the optoelectronic device with the opposite doping type of the first guard ring and the active region, with the second guard ring on the substrate back surface, and with the same doping type of the second guard ring and the substrate back surface into a fifth type of optoelectronic device. The optoelectronic device with the first guard ring of the doping type opposite to the doping type of the active region, the second guard ring on the back of the substrate, and the doping type of the second guard ring opposite to the doping type of the back of the substrate is classified into the sixth type of optoelectronic device.

9. The method of claim 8, wherein, When there is only one first guard ring around the active region, the distance between the first guard ring and the active region is determined as the target spacing; The testing of the different types of optoelectronic devices comprises: The testing obtains the active region leakage current data of each type of optoelectronic device corresponding to the preset voltage range under different target spacings.

10. The method of claim 9, wherein, The testing of the different types of optoelectronic devices comprises: The testing obtains the active region leakage current data of each type of optoelectronic device corresponding to the preset voltage range under different surface recombination rates.

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